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Channel Estimation and Prediction Based Adaptive Wireless Communication Systems
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Wireless channels are typically much more noisy than wired links and subjected to fading due to multipath  propagation which result in ISI and hence high error rate. Adaptive modulation is a powerful technique to improve the tradeoff between spectral efficiency and Bit Error Rate (BER). In order to adjust the transmission rate, channel state information (CSI) is required at the transmitter side.

In this paper the performance enhancement of using linear prediction along with channel estimation to track the channel variations and adaptive modulation were examined. The simulation results shows that the channel estimation is sufficient for low Doppler frequency shifts (<30 Hz), while channel prediction is much more suited at high Doppler shifts with same SNR and target BER=10-4. It was shown that the performance at higher Doppler frequency shifts (<30Hz) was improved by more than 2dB over channel estimation at target BER=10-4 and 32QAM constellation used.

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Publication Date
Tue Dec 22 1998
Journal Name
College Of Education Ibn Rushd
Investigating Iraqi College students&#39; production of English Intra Word and Inter Word Consonant Clusters
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MR Younus, 1998

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Publication Date
Mon Apr 01 2019
Journal Name
Biochemical And Cellular Archives
Prevalence of Hbv, Hcv and Hiv-1, 2 infections among patients in Saladin governorate, Iraq
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Hepatitis B and Hepatitis C viruses are the major health problem in the worldwide. In the Middle East, the prevalence of HBV in general population with the chronic infectionsis 2-5%,whereas the prevalence of HCV is about 1% in Arabian Gulf countries. World Health Organization (WHO) revealed that the risks of HBV and HCV transmissionas well as human immunodeficiency virus (HIV) through the transfusion of contaminated blood and blood products is high, because of the fragility of health services in these countries. Several viral diseases are transportby different modes like bloodtransfusion, sexual contact, and unsafe injections. The mostcommon blood-transmitted viruses are hepatitis B virus(HBV), hepatitis C virus (HCV) and humanimmunodeficie

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Scopus
Publication Date
Sun Dec 30 2018
Journal Name
2018 Computing In Cardiology Conference (cinc)
Theoretical and Experimental Reflection Coefficients in Flexible Tubes as a Function of the Mach Number
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The standard formulation of Wave Intensity Analysis (WIA) assumes that the flow velocity (U) in the conduit is <;<; the velocity of propagation of waves (c) in the system, and Mach number, M=U/c, is negligible. However, in the large conduit arteries, U is relatively high due to ventricular contraction and c is relatively low due to the large compliance; thus M is > 0, and may not be ignored. Therefore, the aim of this study is to identify experimentally the relationship between M and the reflection coefficient in vitro. Combinations of flexible tubes, of 2 m in length with isotropic and uniform circular cross sectional area along their longitudinal axes, were used to present mother and daughter tubes to produce a range of reflection coeffic

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Publication Date
Mon Jan 01 2007
Journal Name
Basrah Journal Of Veterinary Research
Some anatomical and Histological observation on the pineal gland in an Endogenous Moorhen (Gallinula chloro)
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Publication Date
Mon Jan 27 2025
Journal Name
Journal Of Physical Education
The Effect of Daily Timing Variation on some Motor Abilities and Anaerobic Ability among Sabers
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Publication Date
Thu Dec 01 2022
Journal Name
Iraqi Journal Of Statistical Sciences
Use The Coiflets and Daubechies Wavelet Transform To Reduce Data Noise For a Simple Experiment
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In this research, a simple experiment in the field of agriculture was studied, in terms of the effect of out-of-control noise as a result of several reasons, including the effect of environmental conditions on the observations of agricultural experiments, through the use of Discrete Wavelet transformation, specifically (The Coiflets transform of wavelength 1 to 2 and the Daubechies transform of wavelength 2 To 3) based on two levels of transform (J-4) and (J-5), and applying the hard threshold rules, soft and non-negative, and comparing the wavelet transformation methods using real data for an experiment with a size of 26 observations. The application was carried out through a program in the language of MATLAB. The researcher concluded that

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Publication Date
Sun Jan 05 2014
Journal Name
Paripex - Indian Journal Of Research
Effect of heat treatment on the structural and optical properties of CuIn1-xGaxSe thin films
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The structural, optical properties of cupper indium gallium selenite (CuIn1-xGaxSe) have been studied. CuIn1-xGaxSe thin films for x=0.6 have been prepared by thermal evaporation technique, of 2000±20 nm thickness, with rate of deposition 2±0.1 nm/sec, on glass substrate at room temperature. Heat treatment has been carried out in the range (373-773) K for 1 hour. It demonstrated from the XRD method that all the as-deposited and annealed films have polycrystalline structure of multiphase. The optical measurement of the CIGS thin films conformed that they have, direct allowed energy gap equal to 1.7 eV. The values of some important optical parameters of the studied films such as (absorption coefficient, refractive index, extinction coeffici

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Publication Date
Thu Oct 01 2020
Journal Name
The Asian Efl Journal
The Effect of Flow as a Strategy on EFL Student-teachers' Performance and their Flow
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This study aims at suggesting flow as a strategy for training female EFL student-teachers in the teaching training course and finding out the effect of this strategy on their performance and their flow state. The training course syllabuses will be constructed according to the flow nine factors and the teaching skills. The measurement tools are the student-teacher performance checklist that has already been used by the department of English language and SHORT Flow State Scale (S FSS-2). The study population is represented with the (60) female student-teachers/ fourth stage/ evening studies at theEnglish department /college of education for women/the University of Baghdad. The study is used the experimental design in that (30) of the student-

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Scopus
Publication Date
Sat Dec 31 2022
Journal Name
Journal Of Economics And Administrative Sciences
Evaluation of the Strategic Performance of the State Board of Antiquities and Heritage/Case Study
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This research aims to the possibility of evaluating the strategic performance of the State Board for Antiquities and Heritage (SBAH) using a balanced scorecard of four criteria (Financial, Customers, Internal Processes, and Learning and Growth). The main challenge was that the State Board use traditional evaluation in measuring employee performance, activities, and projects. Case study and field interviews methodology has been adopted in this research with a sample consisting of the Chairman of the State Board, 6 General Managers, and 7 Department Managers who are involved in evaluating the strategic performance and deciding the suitable answers on the checklists to analyze it ac

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Publication Date
Sun Dec 19 2021
Journal Name
Iraqi Journal Of Science
Prevalence of anemia and determination of some hematological parameters among pregnant women in Baghdad city
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From 124 women in different stage of pregnancy ,there were 83 (67%) conceded
anemic and 41(33%) were non anemic ,there were 54(65%) suffering from iron
deficiency anemia. According to the form of anemia , 27 (32.5%) were suffering
from mild anemia, 41 (49.4%) moderately anemia while15 (18.1%) severe anemia
The number of anemic pregnant women from Baghdad was 39 (47%) and the
internally displaced anemic pregnant women 44 (53%). the anemic pregnant women
who were primigravida 36 (43.4%), while the pregnant women who were multipart
gravida 47 (56.6%) .The number of anemic pregnant women was 26(31.3%) for age
of 17-27y ,33(39.8%) for age of 28-37y and 24(28.9% )for age of 38-45y .while the
number of anemic pregnant

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